Development of experimental and early investigational drugs for the treatment of Ebola virus infections

Introduction: Ebola virus (EBOV) causes severe hemorrhagic fever in humans, and due to the aggressive nature of infection it has been difficult to develop effective medical countermeasures. Total casualties from past outbreaks numbered fewer than 1500 cases, but EBOV unexpectedly emerged from Guinea in late 2013 and infected over 25,000 people in nine countries spanning Africa, Europe and North America. Concern among the public and authorities helped spark an unprecedented push to fast-track experimental drugs for clinical use. Areas covered: The authors provide a historical timeline of the progress in developing a licensed post-exposure EBOV drug for use in humans. Furthermore, they summarize and discuss the published data with different in light of their potential to play a role during outbreak times. Expert opinion: Monoclonal antibody-based therapy is able to reverse advanced EBOV disease, but the outbreak of an antigenically divergent filovirus would require the reformulation and possibly redevelopment of the most promising candidates. Immunocompetent small animal models have not yet been developed for screening drugs against other filoviruses aside from Ravn and Marburg virus, and thus the number of prophylactic and therapeutic candidates lag behind that of EBOV. There is an urgent need for the proactive development of drugs against other neglected pathogens before the next major outbreak.